Keel column



Nov. 13, 1928.

H. T. KRAFT KEEL COLUMN Filed 00M 20, 1924 s Sheets-Sheet 1 I n a a o a o co Rnu onoooaoou o a a o a n u a n a o a n o a a n o no INVENTOR I lfermanT. Kraft NOW. E3, 1928. 1,691,818

H. T. KRAFT KEEL COLUMN Filed Oct. 20, 1924 s Sheets-Sheet 2 g Q a Q o c Q 0 8 o INVENTOR Herman T. Kraft Patented Nov. 13, 1928..

UNITED HERMAN T. KRAFT, OF AKIEON, OHIO, ASSIGNOR TO THE GOODYEAR TIRE 80 RUBBER COMPANY, OF AKRON, OHIO, A, CORPORATION OF OHIO.

KEEL COLUMN.

Application filed October 20, 1924. Serial No. 744,570.

My invention relates to a keel structure for semi-rigid airships, and it has particular relation to the construction and arrangement of the individual struts, and to means for securing said struts into the desired. relationship to form an airship keel.

One object of my invention consists in forming a novel type of strut, column or girder, which is of relatively light weight, which is simple and inexpensive to make, and which is particularly adapted to withstand great tensile and compressive stresses.

Another object of my invention conslsts in providing a novel type of end fitting whereby the columns or struts which constitute the fabricated structure of the keel are held 1n the desired relationship.

A still further object of my invention consists in forming a novel arrangement of columns or girders and their fittings to form a keel whereby great resistance to the deformation of the keel from any forces whatsoever is obtained with a minimum of weight.

Heretofore, it has been customary to form the keels of semi-rigid airships from built-up columns comprising longtitudinal members and interconnecting lattice work. Such columns have been employed in posltions on the keel where it is desirable to withstand elther longitudinal or lateral stresses.

By my invention, I have provided girders or columns which are specifically adapted to withstand the stresses peculiar to the partlcular position in the keel which they occupy. By such construction, the total weight of the keel may be materially reduced and at the same time the effective strength thereof materially increased.

For a better understanding of my invention, and a detailed description thereof, reference may now be had to the accompanymg drawings, of which Fig. 1 is a side elevational view of one form which my invention may assume;

Fig. 2 is a cross-sectional view of the structure illustrated in Fig. 1, the section being taken along the line II II thereof;

Fig. 3 1s a side elevational view of one of the longitudinally disposed segments of arcuate cross-section, which is employed in the construction of the column illustrated in Fig. 1;

Fig. 4 is a cross-sectional view of the structure illustrated in Fig. 3, the section being taken along the line IVIV thereof;

Fig. 5 is a detailed view of an end connection for a column of the type illustrated in Fig. 1, and is particularly adapted for connecting such column in articulated relationship with a suitable socket or retainer;

Fig. 6 is a cross-sectional view of the column illustrated in Fig. 7, the section being taken along the line VIVI thereof Fig. 7 is a side elevational view of another type of column or girder which I employ in pract1cing my invention;

Fig. 8 is a side elevational view of an end' fitting constructed in accordance with my invention, and adapted for connecting a plurality of columns of various types into a fabrlcated structure;

Fig. 9 is a cross-sectional view of the structure illustrated in Fig. 8, the section being taken along the line IXIX thereof;

Fig. 10 is a perspective view of a portion of a keel constructed in accordance with my invention.

As illustrated particularly in Figs 1 to 4, inclusive, the column shown is composed of a plurality of relatively long members 10, which are arcuate in cross section, .and which are provided at both of the longitudinally extending edges with integral radially outwardly extending flanges 11. The members 10 are composed of a thin light weight strong sheet metal, such, for example, as duralumin. The flanges 11 are provided with a plurality of openings 12 within which rivets 13 are disposed to secure the several segments together to constitute a substantially circular column 14, as best illustrated in Figs. 1 and 2. The sections 10 are arcuate in cross section throughout their length, and each constitutes a quadrant. By reason of the fact that the radius of the central portions of the arcuate sections 10 is greater than is the radius of the end portions thereof, the assembled column 14 is of greater cross section in the central portion thereof than at the ends, and tapers symmetrically toward each end.

Each of the columns 14 is provided at its end with a special end connection 18 as best shown in Figs. 1, 5 and 9. Referring particuvided with an annular collar member 19 which fits snugly therein and is secured thereto'by a plurality of rivets 20. The outer end 21 of the collar member 19 is of slightly smaller diameter than is the main body portion thereof, and is provided with an externally threaded portion 22. A substantially cone-shape memer 23 is provided at its larger end with an internally threaded portion 24 which is adapted to be moved into threaded engagement with the externally threaded portion 22 of the collar 19, and is thereafter secured from movement with respect thereto by means of a cotter pin 25. The smaller end of the conical member 23 is provided with an axial aperture 26,-

the internal surface of which is threaded and is adapted to receive, in threaded engagement, a pin 27. The conical member 23 is provided with an opening within which is disposed a cotter pin 28, by means of which movement of the pin 27 relative to the conical member 23 is prevented. The opposite end 29 of the pin 27 is of segmental spherical contour and is provided, in the central portion thereof,.with a semi-spherical recess 30, as best illustrated in Fi .9.

Re erring now more particularly to Figs. 6 and 7, which illustrate the columns built to withstand the lateral or bending stresses, I have shown a column composed of sheet metal quadrants 35, each of which is provided at its lateral edges with longitudinally extending flanges 36 which are attached together by means of rivets 37 to constitute a column 38. It will be noted that the column 38 is of circular cross section throughout its entire length, but is of the same diameter throughout its length. The flanges 36, on diametrically opposite sides of the column 38," are provlded withreinforcing flange members 39, disposed one on each side of the flange members 36, and secured together and to the flange members 36, by the rivets 37 which extend therethrough. The outer edges 40 of the reinforcing flanges 39 are bent over so as to cause the reinforcing flange members to be of substantially L-shape in cross section.

The columns 38 are not provided with special end fittings which adapt the column for articulated connection, but are provided with perfectly smooth round ends 41, formed by' trimming away the ends .of the flanges 36. which ends are adapted to be received in snug fitting arrangement within cylindrical sockets provided therefor.

Referring particularly to Figs. 8 and 9, it will be observed that I have provided a special end fitting 45 which comprises two integral sockets 46 and 47, which are adapted to receive in telescoping relation the ends of the columns 38 which are secured therein by means of bolts 48. The fitting 45 is also provided with an internally threaded aperture 49, disposed at the intersection of the axes of the columns 38 and extending perpendicularly with respect thereto. The aperture 49 is so designed as to permit of securing therein, in articulated relationship, the end members 18 of the columns 14. The end members 18 are secured against being withdrawn from the aperture by tensile stresses, by means of an externally threaded collar member 50 which fits over the pin 27, and is provided with an internal segmental spherical surface which is engaged by the external surface of the member 29. The aperture in the collar member 50 is sufficiently larger-than the pin 27 so as to permit of relatively free angular movement with respect thereto. A cotter pin 51 serves to prevent rotative movement of the collar member 50 with respect to' the socket 49. Between the ends of the pins 27 of oppositely disposed columns 14 is dis- I of exerting a tension upon the columns 14,

and the ball 52 permits ofexerting a compressive stress thereon. In likemanner, the sockets 46 and 47 serve to transmit lateral stresses from either of the columns 38 to the remainder thereof. p

The fitting member 45 is also provided with a plurality of lugs 55, 56 and 57, towhich may be secured cables for attaching the gas envelope or hull to the keel, and supporting the pilot engine cars from the keel, and for truss wires for bracing the keel structure.

Referring now to Fig. 10, it will be observed that certain of the columns are disposed longitudinally of the keel structure and that certain are disposed laterally thereof. In constructions of this character, it has been found desirable to form the keel of substantially triangular cross section, which is effected by triangular arrangement of laterally disposed columns 60 secured together by means of the longitudinally dis osed columns 61, and truss wires (B). bvious'ly, the longitudinally disposed columns 61 must be capable of withstanding great tensile and -compressive stresses. The laterally disposed columns 60, onthe other hand, must be particularly adapted to withstand lateral stresses. Also, it is highly desirable that the laterally disposed columns 60be secured together into a rigid structure, and these rigid structures may be secured to the longitudinally disposed struts by means of flexible or articulated connections. For this reason, I employ the columns 38 as lateral struts, and employ columns 14 as longitudinal struts. Thus, by means of the end fittings 45, I am enabled to provide a structure which holds the lateral columns in a definite fixed relationship, but which permits of securing the longitudinally extending columns thereto in articulated relationship.

As the longitudinal strut, which connects the apex of the lateral triangles, must also support a portion of the gas pressure exerted upon the fabric that lies upon the upper longitudinal column, this column is provided with flange reinforcements 39 similar to the reinforcements of the columns 38, so that a beam load can be applied to a column designed primarily to take tension and compression.

From the foregoing description, it will be apparent that I have provided novel end fittings which permit of the construction of a fabricated member in which the laterally disposed portions are rigidly secured in position, and the longitudinally disposed portions are secured in articulated relationship,

and in which a very advantageous use of the weight of metal employed is obtained by using for the lateral struts columns ofthe same diameter throughout, provided with flange reinforcement, and by employing the tapered columns for the longitudinal struts.

Although I have illustrated but a single form which my invention may assume, and

have described in detail but a single applica- 7 tion thereof, it will be apparent to those skilled in the art that it is not limited to the construction of semi-rigid airships, but may equally well be adapted to the construction of rigid ships and the various other structures in which fabricated members of light weight and great strength are required, and that minor modifications and changes may be made in my invention without departing from the spirit thereof, or from the scope of the appended claims.

What I claim is:

1. A fabricated structure comprising hollow sheet metal columns, a plurality of said columns being symmetrically tapered, sockets for interconnecting the end portions of a plurality of the columns of similar construction and a socket having a universal joint operatively connected thereto for connection to the remainder of the columns.

2. A fabricated structure comprising hol low sheet metal columns, a plurality of said columns being tapered from the central portions toward the ends thereof, a plurality of said columns being disposed in substantially the same plane, sockets for receiving all of the columns disposed in the same plane and a socket provided with a universal joint operatively connected thereto and attached to the ends of the remainder of said columns.

3. A fabricated structure comprising a plurality of hollow columns, a fitting for the columns having a socket adapted to receive the end of one column and a flexible connection associated with the fitting for securing a second column thereto.

4. A fabricated structure comprising a plu rality of hollow columns, and means for connecting the columns including sockets for receiving the ends of a plurality of columns in telescoping relation, said means also including auniversal jointfor connecting other .columns thereto.

5. A fabricatedstruct-ure comprising a plurality of hollow columns, means for connecting a plurality of the columns including sockets for receiving the ends of a portion of said columns in telescoping relation and a socket adapted for receiving the ends of an additional number of said columns in articulated relation.

ends thereof, and means adapted to receive the ends of a portion of said columns in telescoping relation and to receive the ends of the pemainder of said columns in articulated rela- 8. A fabricatedstructure comprising a plurality of columns, means for rigidly connecting together a plurality of said columns in substantially the sameplane and means for connecting a plurality of the columns in articulated relation to the ends of the rigidly connected columns.

9. A fabricated structure comprising a plurality of columns, sockets for rigidly connecting the ends of a plurality of the columns, sockets for receiving the ends of an additional number of the columns, and means carried by the first named sockets pivotally connecting the ends of the second named sockets.

10. A fabricated structure comprising a plurality of columns, means for rigidly connecting the columns to form a truss polygonal in cross section, an additional plurality of columns extending substantially from the corners of the truss, and u'niversal'joints incorporated in said means for pivotally connecting said additional plurality of columns to each other and to the truss.

11. A fabricated structure comprising a plurality of columns each column including tapered longitudinally disposed sheet metal members of substantially arcuate cross section and provided with flanges riveted to-' gether, a pluralit of columns provided with sockets for rigi ly securing" them together and additional sockets rovided with means for connecting a plurality of the columns to each other and to the first named sockets. V

12. A fabricated structure comprising a plurality of columns each column including tapere l hr itudinally disposed sheet metal members oi substantially arcuate cross section and rovided with flanges riveted together, auxiliary longitudinall extending flanged members secured to the anges of the arcuate members, a plurality of columns pro' vided with sockets rigidly securing them in telescoping relation andadditional sockets provided with means'for plvotally connecttapered longitudinally disposed sheet metal members of substantially arcuate cross section and provided with flanges riveted together, a plurality of polygonal trusses, each including columns provided with sockets for rigid- 1y securing the latter together and additional sockets provided with universal joints connected to the first named plurality of columns, and to the last named sockets.

In witness whereof, I have hereunto signed my name.

HERMAN T. KRAFT. 

